Improvements in fluid pressure supply systems

摘要

891,700. Compressors. BENDIX-WESTINGHOUSE AUTOMOTIVE AIR BRAKE CO. Oct. 3, 1960 [Dec. 1, 1959], No. 33901/60. Class 8(1). A compressor 10 charges reservoirs 48, 88 arranged in parallel to relatively low and high pressures respectively ; the reservoir 48 being charged through ducts 26, 28, 46 and a cut-off valve 32 until a predetermined pressure in the reservoir opens a governor valve 52 and transmits pressure through ducts 50, 54, 56 to a diaphragm 42 which then closes the valve 32 whilst reservoir 88 is charged through ducts 26, 30 and 92 until a predetermined pressure in said reservoir opens a governor valve 84 and transmits pressure through ducts 86, 82 to the inlet cavity 80 of a relay valve 60 and past a valve member 76 thereof to a duct 24 leading to an unloader piston 20 serving to keep open the compressor inlet valve 14, the valve member 76 being held open against a spring 78 by downward displacement of a piston 70 and rod 74 effected by a diaphragm 66 subjected to low pressure reservoir pressure transmitted through the governor valve 52. An adjustable pressure opening valve 104 in the high pressure reservoir charging duct may be set to delay charging until the low pressure reservoir is itself substantially fully charged. During normal working with the compressor inlet valve not unloaded and the governor valves 52, 84 closed the latter vent to atmosphere ducts 54, 82 and hence control cavities 40, 62 of diaphragm 42, 66. The reservoirs 48, 88 may supply compressed air to an air brake system and a starting motor for a diesel engine.